NEW CATALYTIC-SYSTEMS FOR THE FIXATION OF CARBON-DIOXIDE .1. COPOLYMERIZATION OF CO2 AND PROPYLENE-OXIDE WITH NEW RARE-EARTH CATALYSTS-RE(P204)3-AL(I-BU)3-R(OH)N

Copolymerization of propylene oxide and carbon dioxide was successfully carried out by using new rare-earth catalytic systems for the first time. It has been found that ternary rare-earth coordination catalysts composed of rare-earth phosphonate, triisobutylaluminum, and glycerine are effective catalysts for the copolymerization. The system Y(P204)3-Al(i-Bu)3-glycerine shows the highest activity. The yield and intrinsic viscosity of the copolymer depend significantly on the molar ratio of catalyst components and the reaction condition. The copolymers prepared were characterized by IR, H-1 NMR, GPC, and DTA-TGA. It is showed that the copolymers obtained have a high molecular weight with a narrow molecular weight distribution and a high thermal stability. The carbonate unit content of the methanol-insoluble copolymer is as high as 30-40%.